Photonic Crystal Nanobeam Cavity With Stagger Holes for Ultrafast Directly Modulated Nano-Light-Emitting Diodes

A photonic crystal nanobeam cavity with stagger holes in InP/InGaAsP/InP heterostructure is proposed for ultrafast directly modulated nano-light-emitting diodes (nanoLEDs). With stagger holes, the quality factor
Q
can be engineered in the range of 10
²
~ 10
⁴
while keeping a small mode volume (
V
_eff
). As a result, the modulation speed of nanoLEDs can be dramatically improved by a small
V
_eff
to enhanced spontaneous emission (SpE) rate and a moderate
Q
to counterbalance SpE lifetime and photon lifetime of the cavity. In our simulation, the direct modulation bandwidth could be higher than 60 GHz with optimal
Q
value of 2150 and
V
_eff
of 2.3( λ
₀
/2
n
)
³
.